The 'What Makes You Beautiful' singer saw a post that Murs sent to his official Twitter account on May 3, in which he explained that he had been "sparring" with a friend, and joked that he probably "wouldn't knock snow off a rope".

Following Horan's lighthearted remark, Murs shot back with "hahaha true!! I've seen monkeys take better swings!! I was awful!!"

This message prompted Horan to respond with the suggestion that they meet up while on tour in the USA together for a few rounds, and Murs said he is more than up for the challenge:

"It's On mate!! Lets find a gym in america!!"